Resistive random access memory (hereinafter, referred to as ReRAM) in which a variable resistive layer capable of retaining a plurality of resistance states is used in a memory element is known. ReRAM having a three-dimensional structure in which a plurality of nR-1Tr type strings in which a plurality of word lines are disposed on the side surfaces of bit lines, which are disposed perpendicular to a substrate and include select transistors at end portions thereof close to the substrate, in a height direction through variable resistive layers are disposed on the substrate has been proposed in the related art.
Since current flows in the ReRAM during a set operation and a reset operation, the word lines and the bit lines are required to have low resistance. Further, in order to stabilize the operations of the ReRAM, it is effective to employ a bilayer structure which includes a high resistance layer and a low resistance layer. However, in a case where the bilayer structure is applied to the ReRAM having the three-dimensional structure, the miniaturization of the ReRAM having the three-dimensional structure becomes difficult.